Vascular disease has been recognized as one of the major leading causes of death and morbidity in the Western world, and can be expected to be on the rise globally. Atherosclerosis is a specific type of vascular disease that can manifest itself in the accumulation of degenerative material along and throughout the inner linings of vessel walls, and can be accompanied by the formation of plaques comprising variable degrees of fatty, fibrous and/or calcified tissue over time. While the onset of disease may be asymptomatic at first, lesion formation, plaque deposition and subsequent growth can lead to substantial thickening and hardening of blood vessels over time, thereby causing successive reduction of lumen diameter, restriction of blood flow and impairment of vessel flexibility.
Atherosclerosis can occur anywhere in the human body, including the cerebral, carotid, coronary, renal, hepatic, aortoilliac, iliac, gonadal, femoral, and popliteal arteries and veins, and can be differentiated into neurovascular, coronary, or peripheral vascular disease, depending on the affected vascular regions of the body. While the human body can partially compensate the gradual impairment of vascular function by formation of collateral vessels to maintain blood supply to affected tissues and organs, due the progressive nature of the disease, circulatory condition can deteriorate to a stage where dependent organs become inadequately supported. This can lead to variable forms of increasingly worsening health conditions and associated complications over time. For cardiovascular disease, angina pectoris, myocardial infarction (MI) and congenital heart failure may result. Patients suffering from peripheral vascular disease often exhibit, in the order of disease progression, claudication, ischemic rest pain, ulcerations, and may develop critical limb ischemia (CLI), gangrene or tissue necrosis.
As opposed to the more prevalent forms of obstructive vascular disease, the circulatory system can develop other vascular defects that involve the abnormal dilation of blood vessels, such as the formation of aneurysms. Aneurysms are blood-filled vascular protrusions caused by the gradual weakening and subsequent dilation of vessel walls. These malformations can occur at vital regions throughout the human body, including the carotid arteries, aorta and brain. The weakened vessel walls can be susceptible to rupture, potentially resulting in acutely life-threatening complications, such as hemorrhaging, embolisms and strokes. Certain other types of vascular anomalies, such as the formation of a passageway between a vein and an artery, or arteriovenous (AV) fistula, can be congenitally acquired, originate from vessel trauma and inflammation, or be purposely created for therapeutic reasons as a specific form of vascular access for hemodialysis. Patients with AV fistulas or AV grafts may experience complications, such as thrombus formation, vessel narrowing and calcification, frequently requiring vascular intervention in the form of balloon dilation, stent placement, grafting, and/or removal of thrombotic matter to effect revascularization.
Currently, the interventional instruments available to physicians may be adequate; however, some procedural inefficiencies and limitations continue to exist due to the inherent limitations in product design and patient anatomical complexities. There is an unmet need to provide improved medical devices for treating both obstructive and dilative types of vascular diseases.